|About this Abstract
||2017 TMS Annual Meeting & Exhibition
||Phase Transformations and Microstructural Evolution
||F-74: Improved Electrochemical Discharge Kinetics of V-based BCC Metal Hydrides via Microstructure Reduction
||Nicholas Weadock, Heng Yang, Hongjin Tan, Brent Fultz
|On-Site Speaker (Planned)
Vanadium based BCC alloys are a promising high capacity anode material for metal hydride type batteries. Vanadium alloys containing titanium and nickel have been shown to unmix into a microstructure consisting of a majority V-rich region and a minority TiNi region. The TiNi rich region serves as an electrocatalyst to promote hydrogen evolution, which diffuses into the V-rich region to form a metal hydride. Typical alloy preparation via arc melting produces majority V-rich regions on the order of 10 microns within a matrix of TiNi. Reducing the length scale of the unmixing will improve the kinetics of the material by reducing the hydrogen diffusion length and increasing surface area for electrocatalysis. We developed quaternary TiVNiCr alloys produced via suction casting which have improved cycling kinetics over the traditional arc melted alloy. The mechanism for improved kinetics was investigated via SEM, electrochemical methods, and in-situ and ex-situ XRD.
||Planned: Supplemental Proceedings volume